Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
A wireless communication network may include a number of access point that can support communication for a number of mobile devices, such as, for example, mobile stations (STA), laptops, cell phones, PDAs, tablets, etc. A STA may communicate with an access point via the downlink (DL) and uplink (UL). The DL (or forward link) refers to the communication link from the access point to the STA, and the UL (or reverse link) refers to the communication link from the STA to the access point.